I agree glenis the 86 spec spolier looks smoother. Thing is I looked at so many RS the age didnt bother me as long as it was clean. U could buy a 91 H thats rotten or a 86 D thats been wel kept and looked after, which would you rather have?
Also I dont see the point of changing your bumpers to the 90 spec if u have pre 90 because it ruins the originality of the car and takes away its charachteristics. The mechanisms of the 90 spec seem to be an improvement however.